Do you mean you only need a single wheel retract ?, if so does this help -
Or do you mean you just need the steerable nose gear ?. If so try the HobbyKing site, just type, retract, in the search box.

Yes as I said I only require the nose gear assembly – not steerable. It is for a semi scale RF5B Sperber which is a monowheel motorglider. A similar video is where I saw it with the name Lindinger but it is not theirs.

The Hobbyking one is not suitable as it is plastic, has a weight limitation and does not extend down far enough for my model. All the similar glider ones also do not go down far enough either which is why I want to use a nose gear assembly which I can build in to emulate the scale position but not necessarily the action of the real one.

A standard retract with a straight leg has no offset. I want something like these as they have a trailing fork, angles down, that emulates the semi scale action that I am after. I know I can get 1/4 scale ones for the RF4 but these are too big for my model as it is approx 1:6.5 scale